Because the tweet was a response, most of her 5.6 million followers didn't see it -- but it elicited a mix of responses from those who did. While some agreed that Trump exhibits signs of mental illness, others took offense, accusing Dunham of being racist herself.

Although Dunham's comments have drawn some ire, other celebrities have perhaps more effectively called out the president, who last week referred to NFL players who kneel during the national anthem "sons of bitches."

"As a football fan, I am proud of the NFL players today. Nothing is more American than the right to peacefully protest," wrote Ellen DeGeneres.

John Legend went beyond Twitter: The artist penned an editorial for Slate, in which he wrote, "Protest is patriotic. Protest has played a critically important role in elevating the voices of the most vulnerable in our nation. Protest in America has been essential to ending war, to demanding equal rights, to ending unfair practices that keep citizens marginalized. If we quell protest in the name of patriotism, we are not patriots. We are tyrants."

69PHOTOS

Luna Legend, daughter of John Legend and Chrissy Teigen

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Luna Legend, daughter of John Legend and Chrissy Teigen

first week of school 😩 they had us make a little family photo album she can look at when she’s sad or upset. she loves it. my heart ksosksodododosksidojsjskodmskzh

my girl

“Should I post the one where his head looks unsupported but my face looks good and Luna is over it, the one where his head is supported but my face is just okay and Luna is over it, or him crying and my face looks okay and luna is over it?”

👛

Luna and daddy

“an outrageous girl can’t settle for a plain old hat” - Marilyn Monroe probably at some point

🧡

📷 @bumper3077

Making cornflake marshmallow and fruity pebble crunch cookies for @monicarosestyle and @traceycunningham1! From the genius that is @christinatosi and the @milkbarstore cookbook!

*meryl streep voice* “Go.”

Look at these twin humans https://t.co/TX5xto0Gh2

Oh you cheeky face with my same squinty eye!!

❤️

Last day of cookbook shooting!! ❤️❤️❤️ to @aubriepick @monicarosestyle @1maryphillips @laurapolko @patrickta @jenatkinhair @adeenasussman @fannyfoodstyle ahhhhh so many more people

Happy first birthday Lu!!!! My lovebug. You are all the best parts of the both of us and I cannot believe how much has happened in you first 12 months of life. We love you to the luna and back. Thank you @Yopeteryang for taking these awesome photos and the lip sync battle team for such a nice surprise!!! ❤️❤️❤️